197,306 research outputs found
Representations and classification of traveling wave solutions to Sinh-G{\"o}rdon equation
Two concepts named atom solution and combinatory solution are defined. The
classification of all single traveling wave atom solutions to Sinh-G{\"o}rdon
equation is obtained, and qualitative properties of solutions are discussed. In
particular, we point out that some qualitative properties derived intuitively
from dynamic system method aren't true. In final, we prove that our solutions
to Sinh-G{\"o}rdon equation include all solutions obtained in the paper[Fu Z T
et al, Commu. in Theor. Phys.(Beijing) 2006 45 55]. Through an example, we show
how to give some new identities on Jacobian elliptic functions.Comment: 12 pages. accepted by Communications in theoretical physics (Beijing
Interactions of satellite-speed helium atoms with satellite surfaces. 2: Energy distributions of reflected helium atoms
Energy transfer in collisions of satellite-speed (7,000 m/sec) helium atoms with a cleaned 6061-T6 satellite-type aluminum surface was investigated using the molecular-beam technique. The amount of energy transferred was determined from the measured energy of the molecular-beam and the measured spatial and energy distributions of the reflected atoms. Spatial distributions of helium atoms scattered from a 6061-T6 aluminum surface were measured. The scattering pattern exhibits a prominent backscattering, probably due to the gross surface roughness and/or the relative lattice softness of the aluminum surface. Energy distributions of reflected helium atoms from the same surface were measured for six different incidence angles. For each incidence angle, distributions were measured at approximately sixty scattering positions. At a given scattering position, the energy spectra of the reflected helium atoms and the background gas were obtained using the retarding-field energy analyzer
Researches on interactions of satellite-speed helium atoms with aluminum and quartz surfaces
Three major areas were experimentally studied: (1) energy transfer in collisions of satellite-speed (700 m/sec) helium atoms with a cleaned satellite-type aluminum surface was investigated using the molecular-beam technique. Spatial and energy distributions of reflected helium atoms were measured and analyzed, (2) The gross accommodation coefficient for a satellite-speed (7000 m/sec) helium beam entering a 2-inch-diameter aluminum spherical cavity was determined by measuring the exit velocity distribution of the leaving helium atoms using a metastable time-of-flight method. Results indicate that the 7000-m/sec satellite-speed helium atoms entering the cavity gain full accommodation with the room-temperature inner surface of the sphere through a large number of collisions before leaving the spherical cavity; and (3) the feasibility of producing a satellite-speed atomic hydrogen beam by arc-heating, for use in studies of interactions of satellite-surfaces with hydrogen atoms under laboratory conditions, was investigated. It was found that a stable arc-heated molecular hydrogen beam can be obtained using the arc-heater, and that a partially dissociated hydrogen beam can be produced. Photographs of laboratory equipment are shown
Heat transport measurements in turbulent rotating Rayleigh-Benard convection
We present experimental heat transport measurements of turbulent
Rayleigh-B\'{e}nard convection with rotation about a vertical axis. The fluid,
water with Prandtl number () about 6, was confined in a cell which had
a square cross section of 7.3 cm7.3 cm and a height of 9.4 cm. Heat
transport was measured for Rayleigh numbers Ra and Taylor numbers Ta . We show the variation of
normalized heat transport, the Nusselt number, at fixed dimensional rotation
rate , at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed
Rossby number Ro. The scaling of heat transport in the range to about
is roughly 0.29 with a Ro dependent coefficient or equivalently is also
well fit by a combination of power laws of the form .
The range of Ra is not sufficient to differentiate single power law or combined
power law scaling. The overall impact of rotation on heat transport in
turbulent convection is assessed.Comment: 16 pages, 12 figure
Strong gravitational lensing in a squashed Kaluza-Klein black hole spacetime
We investigate the strong gravitational lensing in a Kaluza-Klein black hole
with squashed horizons. We find the size of the extra dimension imprints in the
radius of the photon sphere, the deflection angle, the angular position and
magnification of the relativistic images. Supposing that the gravitational
field of the supermassive central object of the Galaxy can be described by this
metric, we estimated the numerical values of the coefficients and observables
for gravitational lensing in the strong field limit.Comment: 13pages, 5 figures, Final version appeared in PR
A New Species of \u3ci\u3ePediobius\u3c/i\u3e (Hymenoptera: Eulophidae) Parasitizing \u3ci\u3eChyliza Apicalis\u3c/i\u3e (Diptera: Psilidae) in Ash Trees Attacked by \u3ci\u3eAgrilus Planipennis\u3c/i\u3e (Coleoptera: Buprestidae)
Pediobius chylizae, spec. nov. (Hymenoptera: Eulophidae), is described as new and illustrated. This parasitoid has been reared from the puparia of Chyliza apicalis Loew (Diptera: Psilidae) collected from under the bark of ash trees (Oleaceae: Fraxinus spp.) dying after attack by the emerald ash borer, Agrilus planipennis Fairmaire (Coleptera: Buprestidae), an invasive beetle from Asia. This species is compared with related species of Pediobius from the Holarctic Region
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